Neurogenic bladder is a clinical disorder characterized by a dysfunction in the urinary bladder due to a neurologic injury. The urinary bladder is a muscular structure in the hypogastrium that controls the storage and excretion of urine.
The coordinated muscle movement including sphincter control is compromised in the urinary bladder in this disease condition. Neurogenic bladder may present as a progressive loss of bladder control (urinary incontinence) on the release of urine, inability to voluntarily release urine, and urinary frequency. There are cases of congenital neurogenic bladder in infants born with a spinal cord defect (spina bifida) or spinal cord injury.
Any disorder in the central nervous system that affects the brain and the lower body may lead to neurogenic bladder. The following etiology has been noted to amongst the most common:
The incidence of neurogenic bladder is variably dependent on the individual incidences of the primary disease or pathology that gave rise to them. In patients diagnosed with multiple sclerosis, the incidence of neurogenic bladder reaches 20 to 30% within 10 years from diagnosis but for those with detrusor muscle paralysis, 30 to 50% will present in incontinent type of paralysis.
Scientific data have shown that the incidence of neurogenic bladder in Idiopathic Parkinson’s disease (IPD) is 57% to 83% which manifests as incontinence, urgency and frequency symptoms. In traumatic spinal cord injuries, patients will present with some of bladder dysfunction within the year of the trauma in approximately 81% of cases.
Young adults suffering from spina bifida will show signs of urinary incontinence in up to 61% of cases. The incidence of neurogenic bladder in these cases are dependent on the anatomic location of the lesion and the extent of nerve damage.
Neurogenic bladder may occur when the central nervous system sustains damage in the level of the brain, pons, sacral cord and the peripheral nerves. Nerve damage will lead to dysfunctional voiding condition ranging from mild urinary retention to an overactive bladder (OAB).
Urinary incontinence happens when the bladder and sphincters dysfunction. Urge incontinence occurs with a spastic bladder or an overactive one. Uncontrolled voiding with stress incontinence manifests when neurogenic sphincter control and the detrusor muscle is compromised.
Prognosis in neurogenic bladder depends on the level of the nerve damage. The more central (near the brain) the damage the more complications are expected. Brain damage carries a grim outlook because it hampers hormonal control (antidiuretic hormones), regional nervous and muscle control (detrusor muscle, sphincter and the urinary bladder). Surgical methods for neurogenic bladder may give an excellent outlook for the patient.
Hydronephrosis or the hydrostatic enlargement of the kidneys occurs due to the return pressure exerted by the ureters to the kidney when free flow of urine to the bladder is impeded because of a chronic neurogenic bladder condition. Kidney enlargement may lead to renal failure if left untreated and can eventually lead to death. Recurrent urinary tract infections (UTI) may be experienced with vesico-urethral reflux because of sphincter hyperactivity with neurogenic bladders. The most common pathogen in UTI among neurogenic bladder patients are Escherichia coli, Entrococcus and Pseudomonas aeruginosa . The recurrent urinary tract infection is caused by the persistent stasis of urine in the bladder .
The constant urine leakage may cause pressure or bed sores to dependent parts of the skin especially in the back and in the buttocks. Patients with multiple sclerosis succumbs to the incontinent type of neurogenic bladder which are also associated with uterine prolapse among female patients .
Signs and symptoms of neurogenic bladder depends on the nature and the cause of the urinary in continence. These are conveniently divided into two kinds: (A) Symptoms of an overactive bladder which includes urinary frequency, incomplete emptying of bladder, and the progressive loss of bladder control; and, (B) Symptoms of an underactive bladder which include uncontrolled leaks (incontinence), the inability to know if the bladder is full, problems in initiating micturition, and urinary retention.
In the work-up and management of neurogenic bladder, the following diagnostic modalities are used:
Medical management of neurogenic bladder includes the oral intake of bladder relaxants like oxybutynin, and tolterodine for the treatment of a spastic bladder. Botulinum toxins may be used with local infiltration to the bladder to reduce its spasticity . Hyperactive bladders posing with limit urine capacity may benefit from bladder augmentation surgery .
Patients with difficulty initiating and sustaining urination may benefit with an indwelling catheter or an intermittent straight catheterization for easier voiding. A urinary bladder “pacemaker” may be implanted to automatically stimulate its nerves for functionality purposes.
The surgical repair of the sphincter and the sling muscle will improve incontinence issues. For permanent voiding access, a stoma (cystostomy) may be created from the abdomen to the bladder for better and hygienic voiding options. Some variant of cystostomy may have an ileal conduit for better quality of life in patients .
Neurogenic bladder may be prevented only by preventing the primary medical and surgical conditions that cause it. For patients diagnosed with multiple sclerosis, the 10 year interval before signs of neurogenic bladder starts will give enough time for them to do pelvic floor strengthening exercises (Kergel exercises) to improve incontinent problems. Children with neurogenic bladder may be allayed by regular nocturnal emptying of urine to prevent leaks and incontinence .
Patients who have undergone abdominal surgery or those with recent trauma should do early ambulation and exercises to prevent neurogenic bladder from ensuing. Neurogenic bladder with increased risk for recurrent UTI has been found to benefit from bladder inoculation with Escherichia coli antigen which lowers the incidence of UTI episodes per year . Studies have revealed that the regular intake of cranberries tablet has been demonstrated to reduce incidence of UTI in a third of all compliant subjects .
Neurogenic bladder must be viewed as a complication of a primary disease thus any damage to the nerves (spinal) must be brought to medical attention for the proper diagnosis of impending nerve damage. Those diagnosed with neurogenic bladder must learn to identify signs of early urinary tract infection for prompt treatment and averting complications. Catheter and stoma care should always remain sterile to prevent secondary infections.